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Geology and Soils Resource Report Leavenworth National Fish Hatchery Surface Water Intake Fish Screens and Fish Passage Project Environmental Impact Statement Geology and Soils Resource Report U.S. Department of the Interior Bureau of Reclamation Columbia-Pacific Northwest Regional Office 1150 N. Curtis Road Boise, ID 83706 November 2020 Mission Statements The Department of the Interior conserves and manages the Nation’s natural resources and cultural heritage for the benefit and enjoyment of the American people, provides scientific and other information about natural resources and natural hazards to address societal challenges and create opportunities for the American people, and honors the Nation’s trust responsibilities or special commitments to American Indians, Alaska Natives, and affiliated island communities to help them prosper. The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. Executive Summary The U.S. Department of the Interior, Bureau of Reclamation (Reclamation) has prepared an Environmental Impact Statement (EIS) for the Leavenworth National Fish Hatchery (hereafter, LNFH or Hatchery) Surface Water Intake Fish Screens and Fish Passage (SWISP) Project (Map A-1 in Appendix A). The purpose of this specialist report is to provide a comprehensive environmental baseline and analysis of the potential impacts of the SWISP Project under four separate alternatives, including Alternative A, No Action. The Analysis Area for geology and soils includes areas that would be directly impacted by ground disturbance from construction (Map A-9 in Appendix A). The indicator for soils is the acres of soils disturbed by short- and long-term Project components. The indicator for geology is geologic issues, such as movement of natural materials (e.g. erosion) due to construction or Project design. The soils in the Analysis Area are primarily loamy sands, gravelly sandy loam, river-wash, and rock outcrop (no soil cover; USDA 2020). The Analysis Area is located on Mount Stuart batholith, a granodiorite batholith that is stable and cohesive (Tabor et al. 1987). Under the No Action alternative, no new impacts to geologic materials or soils would occur. Under the action alternatives, the construction of Project components, temporary access roads, storage and work areas, and the cut and cover replacement of sections of conveyance pipeline would result in short and long-term effects to soils and geology. Impacts to soils would include compaction and disturbance from roads and construction. Impacts to geology would include the movement of geologic materials from construction and intake operation. Under the action alternatives, approximately 0.18 acres of soils and geologic material would be permanently disturbed. Best Management Practices would reduce the intensity of impacts; however, the placement of permanent Project facilities would continue to result in the irretrievable commitment of soil resources in some areas under all action alternatives. SWISP Project EIS ES-1 Geology and Soils Resource Report Executive Summary This page intentionally left blank. ES-2 SWISP Project EIS Geology and Soils Resource Report Table of Contents Chapter Page EXECUTIVE SUMMARY ....................................................................................................... ES-1 CHAPTER 1. GENERAL PROJECT INFORMATION ...................................................................... 1 1.1 Project Area .......................................................................................................................... 1 1.2 Alternatives ........................................................................................................................... 1 1.2.1 Alternative A – No Action ................................................................................... 1 1.2.2 Alternative B – Proposed Action......................................................................... 3 1.2.3 Alternative C ........................................................................................................... 7 1.2.4 Alternative D .......................................................................................................... 8 CHAPTER 2. RELEVANT LAWS, REGULATIONS, AND POLICY .................................................. 11 2.1 Federal Laws, Regulations, Statutes, and Orders ..........................................................11 2.2 State and Local Laws .........................................................................................................11 CHAPTER 3. AFFECTED ENVIRONMENT .................................................................................13 3.1 Analysis Area ......................................................................................................................13 3.2 Affected Environment ......................................................................................................13 CHAPTER 4. ENVIRONMENTAL CONSEQUENCES ...................................................................15 4.1 Methods ..............................................................................................................................15 4.1.1 Analysis Indicators ...............................................................................................15 4.1.2 Issue Statements ...................................................................................................15 4.2 Alternative A – No Action Alternative ..........................................................................15 4.3 Alternative B – Proposed Action ....................................................................................15 4.4 Alternative C.......................................................................................................................16 4.5 Alternative D ......................................................................................................................16 4.6 Short-Term Uses and Long-Term Productivity ............................................................16 4.7 Unavoidable Adverse Impacts .........................................................................................17 4.8 Irreversible and Irretrievable Commitment of Resources ...........................................17 CHAPTER 5. GLOSSARY ...........................................................................................................19 CHAPTER 6. REFERENCES CITED ...........................................................................................21 Figures Page Figure 1. Geologic Map of the Leavenworth, Washington, Area ..........................................................14 SWISP Project EIS i Geology and Soils Resource Report Table of Contents Appendices Appendix A. Maps Appendix B. Best Management Practices ii SWISP Project EIS Geology and Soils Resource Report Acronyms and Abbreviations Full Phrase BMP Best Management Practice cfs cubic feet per second CIPP cure-in-place pipe COIC Cascade Orchard Irrigation Company Ecology Washington Department of Ecology EPA U.S. Environmental Protection Agency ESA Endangered Species Act EIS Environmental Impact Statement Forest Service U.S. Department of Agriculture, Forest Service IO&MA Intake Operations and Maintenance Area LNFH, Hatchery Leavenworth National Fish Hatchery NMFS National Marine Fisheries Service NPDES National Pollution Discharge Elimination System O&M operations and maintenance PISMA pipeline intake and sediment management area Reclamation U.S. Department of the Interior, Bureau of Reclamation SWISP Surface Water Intake Fish Screens and Fish Passage USACE U.S. Army Corps of Engineers USFWS U.S. Fish and Wildlife Service WDFW Washington Department of Fish and Wildlife SWISP Project EIS iii Geology and Soils Resource Report Table of Contents This page intentionally left blank. iv SWISP Project EIS Geology and Soils Resource Report Chapter 1. General Project Information The U.S. Department of the Interior, Bureau of Reclamation (Reclamation) has prepared an Environmental Impact Statement (EIS) for the Leavenworth National Fish Hatchery (hereafter, LNFH or Hatchery) Surface Water Intake Fish Screens and Fish Passage (SWISP) Project (Map A-1 in Appendix A). The purpose of this specialist report is to provide a comprehensive environmental baseline and analysis of the potential impacts of the SWISP Project under four separate alternatives, including Alternative A, No Action. 1.1 Project Area The Project Area is on and near the LNFH, near the City of Leavenworth in Chelan County, Washington. The Project Area includes the LNFH’s surface water intake and primary point of diversion on Icicle Creek, and conveyance pipeline to the Hatchery. The surface water intake is on U.S. Fish and Wildlife Service (USFWS) property, while the conveyance pipeline crosses several private parcels before re-entering USFWS property. Access to private parcels is via existing easement agreements between the landowner and federal government. The Project Area also includes approximately 1.25 miles of Icicle Creek Road, from the surface water intake to a U.S. Department of Agriculture Forest Service (Forest Service) kiosk to the west, as well as access roads and staging areas on the USFWS property. The Project Area is depicted on Map A-1 in Appendix A. 1.2 Alternatives Reclamation identified a reasonable range of alternatives for analysis in the EIS through the development of screening criteria, the assessment of
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